If the Control/Status Stream is enabled, checking this allows AXI DMA to use a receive length field that is supplied by the S2MM target IP in the App4 field of the status packet. This gives AXI DMA a pre-determined receive byte count, allowing AXI DMA to command the exact number of bytes to be transferred.
This option provides for a higher bandwidth solution for systems needing greater throughput. In this configuration, the S2MM target IP can supply all data bytes specified in the receive length field of status packet APP4.